The present invention relates to an elongated rod feeding machine for feeding the elongated rod member or bar member to a working machine such as an automatic lathe, and more particularly, to an apparatus for rotatably supporting the elongated member and for continuously supplying the same to the working machine. The apparatus is applied to the elongated rod feeding machine for feeding the elongated rod to the working machine.
When an elongated member or a long bar is subjected to machining by a working machine such as an automatic lathe, the bar member must be rotationally supported. For the purpose, the rod feeding machine is provided adjacet the lathe for continuously feeding the elongated member thereinto and for rotatably supporting the same during machining.
According to a conventional rod supporting structure, the rod feeding machine is provided with a single elongated support tube which allows insertion of the elongated member thereinto along its entire length for rotatably supporting the elongated member by the entire inner peripheral surface of the support tube. Pressurized oil is filled in the interior of the support tube, and the elongated member in the tube is floatingly and rotatably supported by the swirling oil flow in the support tube.
However, in the conventional structure, only a low speed rotation is available, and if the elongated member is bent and if the bending exceeds a tolerable range, it would be impossible to floatingly support the elongated member due to insufficient oil swirling motion. Further, if excessively bending rod is inserted into the support tube, the rod provides excessively offsetting rotation, by which the rod may but-contact with the inner surface of the support tube. Accordingly, it would be impossible to perform machining. In other words, in the conventional apparatus, only a linearly extending member is applicable to the supporting structure.
In another aspect, according to the conventional rod feeding machine, when a new elongated rod member m is required to be placed on the rod feeding machine F, the rod be inserted from an upstream end F' of the rod feeding machine as shown in FIG. 10(a). (Here, the term "upstream" is defined with respect to rod feeding direction to the working machine.) Therefore, sufficient axial space is required so as to initially place the rod to the upstream side of the feeding machine F, which space has a length l which is substantially equal to an axial length of the rod feeding machine. Alternatively, the rod feeding machine has an upstream portion F" provided with pivot mechanism P, to thus offset the downstream end of the feeding machine L from the upstream end of the working machine. As a result, the elongated member is insertable into the rod feeding machine from its downstream end F"' thereof as shown in FIG. 10(b).
With this structure, even though the space having a length l in FIG. 10(a) is not required, it would be rather troublesome to install a new elongated member into the rod feeding machine. Further, lateral space is also required for allowing pivotal movement of the rod feeding machine, which space is not required during machining, but required only at the installation of the rod into the feeding machine.